The decontamination and sterilisation of skin is one of the most important parts of any surgical operation. Since the work of Pasteur, Lister, Semmelweiss and others, we have known that bacteria cause infection. As a consequence of their work, a variety of methods are now routinely used to reduce the bacterial count on the surface of the skin prior to surgical procedures.
Standard techniques employed to this end include: skin depilation (i.e. removal of hair) immediately prior to surgery; removal of any visible contamination; washing of the skin with soap and water; painting of the skin with an anti-microbial agent.
This last part of the preparation before surgery (i.e. the use of an anti-microbial agent) is often known amongst surgeons as the ‘skin prep’. It is this procedure that has turned surgery from a life-threatening procedure into the safe procedure it is today. Prior to the introduction of skin prep, mortality rates from wound infection could be as high as 40%. Following the introduction of skin preparation, the infection rate from bacteria residing on the skin has fallen to almost unrecordable levels.
However, the introduction of more complex surgery, and especially joint-replacement surgery, where the presence of foreign material in the body potentiates the infection, has led to a reassessment of skin preparation.
It is known that anti-microbial agents such as iodine, chlorhexidine and alcohol need time in contact with the skin to kill the bacteria. It is also known that there is a reservoir of skin-associated organisms that reside in the sweat glands and hair follicles of the body. Therefore, a skin preparation agent that stays on the skin for a period of time prior to surgery will be more effective in reducing the bacterial count. Furthermore, if the agent forms a film on the skin which is retained throughout the operation, then this is also of benefit.
A common technique for application of the anti-microbial agent is as follows: the surgeon or the surgeon's assistant is supplied with a bowl containing the skin preparation fluid, and something for applying the agent. This usually comprises a swab or a piece of sponge held in a pair of locking forceps. For preparation of the abdomen or chest, this is usually excellent. The area to be cleaned is roughly flat, does not need to be moved, and is clearly visible to the surgeon.
For structures such as the arm and leg, the situation is more difficult. As the skin prep is carried out after anaesthesia has commenced, the limb must be held in the air by an assistant. It is not possible to clearly see the entire surface of limb. In particular, toes and fingers are difficult to prepare. The person who holds the limb is ‘non-sterile’—i.e. has not been through the de-contamination procedures carried out by surgeons and their assistants—and so has to transfer the support of the limb to the sterile surgical team. This whole procedure takes a significant amount of time and can be prone to contamination. If a tourniquet is being used, then the anti-microbial agent can seep under the tourniquet and cause contact burns.
Whilst lifting of an arm is not too difficult, lower limbs have considerable weight and may have to be supported whilst the limb is cleaned. As a result, the non-sterile member of the team initially supporting the limb may have to support it at arm's length to allow the surgical team access to the limb. This can be dangerous, not only for the patient, if the leg is dropped, but also to the person holding the limb, and can result in back strain and other similar injuries.
Whilst these problems, and the solutions provided by the current invention, are described in terms of human surgical procedures, they clearly have parallels in the veterinary field.
Furthermore, whilst the invention relates primarily to problems associated with the application of anti-microbial agents to limbs, there are similar problems in associated areas for which the invention has considerable application. For example, it is often required to apply other agents such as medicaments, depilants (hair-removal agents) and cosmetic preparations such as artificial tanning solutions to limbs of users, without undue contact of the agent with the hand of the person applying it. Furthermore, these agents may need to be left in contact with the skin for some length of time without the agent drying or coming into contact with, for example, clothes, furniture or other parts of the body. The invention also has application as temporary wound-dressing, for example in the treatment of burns, and allows wound inspection following surgery or during ward rounds. Prior art known to the applicant comprises former patent applications GB 2276323, WO 03/090598, DE 29913123U1 and, U.S. Pat. No. 6,276,364 and U.S. Pat. No. 5,592,953
It is an object of the present invention to attempt a solution to these problems.